/**
 * 线段包含判断
 * @param  {Number}  x0
 * @param  {Number}  y0
 * @param  {Number}  x1
 * @param  {Number}  y1
 * @param  {Number}  lineWidth
 * @param  {Number}  x
 * @param  {Number}  y
 * @return {Boolean}
 */
export function containStroke(x0, y0, x1, y1, lineWidth, x, y) {
  if (lineWidth === 0) {
    return false;
  }
  let _l = lineWidth;
  let _a = 0;
  let _b = x0;
  // Quick reject
  if ((y > y0 + _l && y > y1 + _l) || (y < y0 - _l && y < y1 - _l) || (x > x0 + _l && x > x1 + _l) || (x < x0 - _l && x < x1 - _l)) {
    return false;
  }

  if (x0 !== x1) {
    _a = (y0 - y1) / (x0 - x1);
    _b = (x0 * y1 - x1 * y0) / (x0 - x1);
  } else {
    return Math.abs(x - x0) <= _l / 2;
  }
  let tmp = _a * x - y + _b;
  let _s = (tmp * tmp) / (_a * _a + 1);
  return _s <= ((_l / 2) * _l) / 2;
}
